More than 1,300 hundred scientists have contributed to a new United Nations' report on the state of the world's ecosystems. We look at this "report card" for Earth. And we'll hear about a second U.N. report that recommends immediate steps we should take to protect our environment and encourage sustainable economic development.
Don J. Melnick, executive director, Center for Environmental Research and Conservation; Thomas Hunt Morgan professor of conservation biology. Department of Ecology, Evolution, and Environmental Biology, Columbia University
Carmen Revenga, senior freshwater scientist, The Nature Conservancy
Robert Watson, chief scientist, The World Bank